Tesla blood pumps demonstrate a reduced propensity for hemolysis and thrombosis compared with vane blood pumps. Considering the restricted driving force within the secondary flow channel of vane blood pumps, along with the low hydraulic efficiency of conventional Tesla blood pumps and their internal flow characteristics that significantly contribute to hemolysis and thrombosis, this study introduces a set of vanes atop the rotor of the Tesla blood pump. This forms a dual-fluid domain rotor, and an axial dual-outlet volute shell structure is adopted to realize the separation of the fluid domains. Through numerical simulations of the new structure, a comparative analysis was conducted in this study on the internal flow characteristics of double-outlet and single-outlet volute shells, and symmetric and asymmetric cross-sections of the same rotor. The results indicate that the flow field distribution is more uniform under the double-outlet volute shell structure, and overall energy dissipation is decreased. After implementing the double-outlet design, in the asymmetric cross-section, compared with the symmetric cross-section, the fluid velocity gradient and turbulent kinetic energy at the tongue of the septum are reduced, and the fluid velocity gradient at the convergence of the diffuser tube outlets are also decreased. The maximum scalar stress is lower, and the decline in head and efficiency is mitigated. Moreover, compared with the single-outlet volute shell, the hemolysis index in the asymmetric cross-section is reduced. In summary, this paper proposes a novel dual-outlet centrifugal disk blood pumps, which can provide a reference for the structural design and performance optimization of magnetically levitated centrifugal blood pumps.
Heart-Assist Devices ; Humans ; Equipment Design ; Hemolysis ; Computer Simulation

OBJECTIVE: To explore the feasibility of using biomechanical indicators as supplementary evaluation to the Musculoskeletal Tumor Society Scoring System (MSTS) for amputee patients. METHODS: Twenty-four patients who underwent hemipelvectomy between September 2018 and January 2025 were enrolled. There were 15 males and 9 females with an average age of 61.4 years (range, 45-76 years). Participants performed gait tests at self-selected speeds using three assistive devices (prosthesis, single crutch, and double crutches). Motion data were analyzed using a customized OpenSim model. Biomechanical indicators of the intact limb exhibiting common characteristics were screened through correlation and sensitivity analyses. Test-retest reliability [interclass correlation coefficient (ICC)] of selected parameters was assessed to evaluate their potential as MSTS score supplements. RESULTS: All biomechanical indicators showed significant positive correlations with MSTS scores across assistive devices ( P<0.05). Seven indicators demonstrated |Pearson correlation coefficients|>0.8, including walking speed, maximum hip angle, maximum hip moment, peak hip flexion moment, peak hip extension moment, hip flexion impulse, and hip extension impulse. Among these, maximum hip moment, hip flexion impulse, and hip extension impulse exhibited significant between-group differences in adjacent MSTS levels ( P<0.05), indicating high sensitivity, along with excellent test-retest reliability (ICC>0.74, P<0.01). CONCLUSION Biomechanical indicators statistically qualify as potential supplements to MSTS scoring. Maximum hip moment, hip flexion impulse, and hip extension impulse demonstrate particularly high sensitivity to MSTS score variations.
Humans ; Male ; Middle Aged ; Female ; Aged ; Biomechanical Phenomena ; Amputees/rehabilitation* ; Feasibility Studies ; Artificial Limbs ; Reproducibility of Results ; Amputation, Surgical ; Crutches ; Gait

OBJECTIVES: A ventricular assist device (VAD) is an electromechanical device used to assist cardiac blood circulation, which can be employed for the treatment of end-stage heart failure and is most commonly placed in the left ventricle. Despite enhancing perfusion performance, the implantation of left ventricular assist device (LVAD) transforms the local intraventricular flow and thus may increase the risk of thrombogenesis. This study aims to investigate fluid-particle interactions and thromboembolic risk under different LVAD configurations using three-dimensional (3D) reconstruction models, focusing on the effects of outflow tract orientation and blood flow rates. METHODS: A patient-specific end-diastolic 3D reconstruction model was initially constructed in stereo lithography (STL) format using Mimics software based on CT images. Transient numerical simulations were performed to analyze fluid-particle interactions and thromboembolic risks for LVAD with varying outflow tract orientations under 2 flow rates (4 L/min and 5 L/min), using particles of uniform size (2 mm), and a blood flow rate optimization protocol was implemented for this patient. RESULTS: When the LVAD flow rate was 5 L/min, helicity and flow stagnation of the blood flow increased the particle residence time (RT) and the risk of thrombogenesis of the aortic root. The percentage of particles traveling toward the brachiocephalic trunk was up to 20.33%. When the LVAD flow rate was 4 L/min, blood turbulence in the aorta was reduced, the RT of blood particles was shortened, and then the percentage of particles traveling toward the brachiocephalic trunk decreased to 10.54%. When the LVAD blood flow rate was 5 L/min and the direction of the outflow pipe was optimal, the RT of blood particles was shortened, and then the percentage of particles traveling toward the brachiocephalic trunk decreased to 11.22%. A 18-month follow-up observation of the patient revealed that the LVAD was in good working order and the patient had no complications related to the implantation of LVAD. CONCLUSIONS Implantation of LVAD results in a higher risk of cerebral infarction; When implanting LVAD with the same outflow tract direction, optimizing flow velocity and outflow tract can reduce the risk of cerebral infarction occurrence.
Heart-Assist Devices/adverse effects* ; Humans ; Heart Failure/physiopathology* ; Blood Flow Velocity ; Thromboembolism/prevention & control* ; Models, Cardiovascular ; Heart Ventricles/physiopathology* ; Imaging, Three-Dimensional

OBJECTIVES: Managing patients with refractory head and neck cancer pain is one of the more challenging issues in clinical practice, and traditional intrathecal drug delivery also fails to provide adequate analgesia. There are currently no comprehensive and effective treatment methods. This study aims to observe the efficacy and safety of treating intractable head and neck cancer pain with morphine pump via lumbar approach to the prepontine cistern. METHODS: A total of 18 patients with intractable head and neck cancer pain treated with prepontine cistern morphine pumps were selected from the Department of Pain Management, Second Xiangya Hospital, Central South University between September 2019 and July 2023. Statistical analysis was performed on patients' preoperative and postoperative (1 week, 1 month, and 2 months after surgery), Numerical Rating Scale (NRS) scores, Self-Rating Depression Scale (SDS) scores, daily oral morphine consumption, the number of daily breakthrough pain episodes, and postoperative daily intrathecal morphine dosage. RESULTS: The NRS scores, SDS scores, daily oral morphine consumption, and the number of daily breakthrough pain episodes of patients at each time point after surgery were significantly lower than before surgery (all P<0.05). With the gradual increase in the dosage of intrathecal morphine, the daily oral morphine consumption of patients at each postoperative time point was significantly reduced compared to preoperative levels (all P<0.05). The complications related to the operation were mild, including nausea in 5 cases (31.3%), headache in 2 cases (12.5%); hypotension, urine retention, hypersomnia and constipation in 1 case (6.3% each), and no serious adverse events occurred. All improved and were discharged after symptomatic treatment. CONCLUSIONS The implantation of prepontine cistern morphine pump effectively controls intractable head and neck cancer pain, demonstrating characteristics of minimal invasiveness, mild side effects, and low medication dosage under the premise of standardized procedures.
Humans ; Morphine/administration & dosage* ; Male ; Female ; Middle Aged ; Head and Neck Neoplasms/surgery* ; Analgesics, Opioid/administration & dosage* ; Cancer Pain/drug therapy* ; Pain, Intractable/etiology* ; Aged ; Adult ; Infusion Pumps, Implantable ; Pain Management/methods*

Extracorporeal membrane oxygenation (ECMO) is primarily used in clinical practice to provide continuous extracorporeal respiratory and circulatory support for patients with severe heart and lung failure, thereby sustaining life. It is a key technology for managing severe heart failure and respiratory failure that are difficult to control. With the accumulation of clinical experience in ECMO for circulatory and/or respiratory support, as well as advancements in biomedical engineering technology, more portable and stable ECMO devices have been introduced into clinical use, benefiting an increasing number of critically ill patients. Although ECMO technology has become relatively mature, the timing of ECMO initiation, management of sudden complications, and monitoring and early warning of physiological indicators are critical factors that greatly affect the therapeutic outcomes of ECMO. This article reviews traditional methods and artificial intelligence techniques used in risk assessment related to ECMO, including the latest achievements and research hotspots. Additionally, it discusses future trends in ECMO risk management, focusing on six key areas: multi-center and prospective studies, external validation and standardization of model performance, long-term prognosis considerations, integration of innovative technologies, enhancing model interpretability, and economic cost-effectiveness analysis. This provides a reference for future researchers to build models and explore new research directions.
Extracorporeal Membrane Oxygenation ; Humans ; Artificial Intelligence ; Risk Assessment ; Respiratory Insufficiency/therapy* ; Heart Failure/therapy*

Cardiovascular risk assessment is a basic tenet of the prevention of cardiovascular disease. Conventional risk assessment models require measurements of blood pressure, blood lipids, and other health-related information prior to assessment of risk via regression models. Compared with traditional approaches, fundus photograph-based cardiovascular risk assessment using artificial intelligence (AI) technology is novel, and has the advantages of immediacy, non-invasiveness, easy performance, and low cost. The Health Risk Assessment and Control Committee of the Chinese Preventive Medicine Association, in collaboration with the Chinese Society of Cardiology and the Society of Health Examination, invited multi-disciplinary experts to form a panel to develop the present consensus, which includes relevant theories, progress in research, and requirements for AI model development, as well as applicable scenarios, applicable subjects, assessment processes, and other issues associated with applying AI technology to assess cardiovascular risk based on fundus photographs. A consensus was reached after multiple careful discussions on the relevant research, and the needs of the health management industry in China and abroad, in order to guide the development and promotion of this new technology.
Humans ; Cardiovascular Diseases/prevention & control* ; Artificial Intelligence ; Consensus ; Risk Factors ; Heart Disease Risk Factors

The impeller, as a key component of artificial heart pumps, experiences high shear stress due to its rapid rotation, which may lead to hemolysis. To enhance the hemolytic performance of artificial heart pumps and identify the optimal combination of blade parameters, an optimization design for existing pump blades is conducted. The number of blades, outlet angle, and blade thickness were selected as design variables, with the maximum shear stress within the pump serving as the optimization objective. A back propagation (BP) neural network prediction model was established using existing simulation data, and a grey wolf optimization algorithm was employed to optimize the blade parameters. The results indicated that the optimized blade parameters consisted of 7 impeller blades, an outlet angle of 25 °, and a blade thickness of 1.2 mm; this configuration achieved a maximum shear stress value of 377 Pa-representing a reduction of 16% compared to the original model. Simulation analysis revealed that in comparison to the original model, regions with high shear stress at locations such as the outer edge, root, and base significantly decreased following optimization efforts, thus leading to marked improvements in hemolytic performance. The coupling algorithm employed in this study has significantly reduced the workload associated with modeling and simulation, while also enhancing the performance of optimization objectives. Compared to traditional optimization algorithms, it demonstrates distinct advantages, thereby providing a novel approach for investigating parameter optimization issues related to centrifugal artificial heart pumps.
Neural Networks, Computer ; Algorithms ; Heart-Assist Devices ; Hemolysis ; Humans ; Equipment Design ; Stress, Mechanical ; Computer Simulation

Heart failure (HF),a chronic progressive disease,is a global health problem and the leading cause of deaths in the global population.The pathophysiological abnormalities of HF mainly include abnormal cardiac structure (myocardium and valves),disturbance of electrophysiological activities,and weakened myocardial contractility.In addition to drug therapy and heart transplantation,interventional therapies can be employed for advanced-stage HF,including transcatheter interventions and mechanical circulatory assist devices.This article introduces the devices used for advanced HF that have been marketed or certified as innovative or breakthrough devices around the world and summarizes the research status and prospects the trend in this field.As diversified combinations of HF devices are used for the treatment of advanced HF,considerations regarding individualized HF therapy,risk-benefit evaluation on device design,medical insurance payment,post-market supervision system,and protection of intellectual property rights of high-end technology are needed,which will boost the development of the technology and industry and benefit the patients.
Humans ; Heart-Assist Devices ; Heart Failure/therapy* ; Heart Transplantation ; Myocardium ; Chronic Disease

Objective: Explore the relationship between tip of the left bundle branch pacing lead and anatomic location of left bundle branch as well as the mechanism of left bundle branch current of injury. To clarify the clinical value of left bundle branch current of injury during operation. Methods: The pacing leads were implanted in the hearts of two living swines. Intraoperative electrophysiological study confirmed that the left bundle branch or only the deep left ventricular septum was captured at low output. Immediately after operation, the gross specimen of swine hearts was stained with iodine to observe the gross distribution of His-purkinje conduction system on the left ventricular endocardium and its relationship with the leads. Subsequently, the swine hearts were fixed with formalin solution, and the pacing leads were removed after the positions were marked. The swine hearts were then sectioned and stained with Masson and Goldner trichrome, and the relationship between the anatomic location of the conduction system and the tip of the lead was observed under a light microscope. Results: After iodine staining of the specimen, the His-purkinje conduction system was observed with the naked eye in a net-like distribution, and the lead tip was screwed deeply and fixed in the left bundle branch area of the left ventricular subendocardium in the ventricular septum. Masson and Goldner trichrome staining showed that left bundle branch pacing lead directly passed through the left bundle branch when there was left bundle branch potential with left bundle branch current of injury, while it was not directly contact the left bundle branch when there was left bundle branch potential without left bundle branch current of injury. Conclusion: The left bundle branch current of injury observed on intracardiac electrocardiogram during His-purkinje conduction system pacing suggests that the pacing lead directly contacted the conduction bundle or its branches, therefore, the captured threshold was relatively low. Left bundle branch current of injury can be used as an important anatomic and electrophysiological evidence of left bundle branch capture.
Animals ; Swine ; Bundle of His/physiology* ; Ventricular Septum ; Cardiac Pacing, Artificial ; Heart Conduction System ; Electrocardiography ; Iodine

OBJECTIVE: To explore the design points of a three-dimensional (3D) printed customized cementless intercalary endoprosthesis with an intra-neck curved stem and to evaluate the key points and mid-term effectiveness of its application in the reconstruction of ultrashort bone segments in the proximal femur. METHODS: Between October 2015 and January 2021, 17 patients underwent reconstruction with a 3D printed-customized cementless intercalary endoprosthesis with an intra-neck curved stem. There were 11 males and 6 females, the age ranged from 10 to 76 years, with an average of 30.1 years. There were 9 cases of osteosarcoma, 4 cases of Ewing sarcoma, 2 cases of chondrosarcoma, 1 case of liposarcoma, and 1 case of myofibroblastoma. The disease duration was 5-14 months, with an average of 9.5 months. Enneking staging included 16 cases of stage ⅡB and 1 case of stage ⅢB. The distances from the center of the femoral head to the body midline and the acetabular apex were measured preoperatively on X-ray images. Additionally, the distances from the tip of the intra-neck curved stem to the body midline and the acetabular apex were measured at immediate postoperatively and last follow-up. The neck-shaft angle was also measured preoperatively, at immediate postoperatively, and at last follow-up. The status of osseointegration at the bone-prosthesis interface and bone growth into the prosthesis surface were assessed by X-ray films, CT, and Tomosynthesis-Shimadzu metal artefact reduction technology (T-SMART). The survival status of the patients, presence of local recurrence or distant metastasis, and occurrence of postoperative complications were assessed. The recovery of lower limb function was evaluated pre- and post-operatively using the Musculoskeletal Tumor Society (MSTS) scoring system, and pain relief was evaluated using the visual analogue scale (VAS) scores. RESULTS: The patient's femoral resection length was (163.1±57.5) mm, the remaining proximal femoral length was (69.6±9.3) mm, and the percentage of femoral resection length/total femoral length was 38.7%±14.6%. All 17 patients were followed up 25-86 months with an average of 58.1 months. During the follow-up, 1 patient died of lung metastasis at 46 months postoperatively, and the remaining 16 patients survived tumor-free. There was no complication such as periprosthetic infection, delayed incision healing, aseptic loosening, prosthesis fracture, or periprosthetic fracture. No evidence of micromotion or wear around the implanted stem of the prosthesis was detected in X-ray and T-SMART evaluations. There was no significant radiolucent lines, and radiographic evidence of bone ingrowth into the bone-prosthesis interface was observed in all stems. There was no significant difference in the distance from the tip of the curved stem to the body midline and the apex of the acetabulum at immediate postoperatively and last follow-up compared with the distance from the center of the femoral head to the body midline and the apex of the acetabulum before operation, respectively (P>0.05), and there was no significant difference in the above indexes between immediate postoperatively and last follow-up (P>0.05). The differences in the neck-shaft angle at various time points before and after operation were also not significant (P>0.05). At last follow-up, the MSTS score was 26.1±1.2 and the VAS score was 0.1±0.5, which were significantly improved when compared with those before operation [19.4±2.1 and 5.7±1.0, respectively] (t=14.735, P<0.001; t=21.301, P<0.001). At last follow-up, none of the patients walked with the aid of crutches or other walkers. CONCLUSION The 3D printed customized cementless intercalary endoprosthesis with an intra-neck curved stem is an effective method for reconstructing ultrashort bone segments in the proximal femur following malignant tumor resection. The operation is reliable, the postoperative lower limb function is satisfactory, and the incidence of complications is low.
Female ; Male ; Humans ; Child ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged ; Femur/surgery* ; Lower Extremity ; Bone-Implant Interface ; Femur Head ; Artificial Limbs